Centrifugal evaporation

Abstract

A centrifugal evaporator is described comprising an enclosure having at least one swinging support rotatable therein and adapted to receive and support at least one microtitre well plate thereon. An infra red radiation source is operated during centrifuging to direct radiation towards the support. A removable shroud is fitted over the well plate and cooperates with the swinging support to form an enclosure which is impervious to direct penetration of radiation from the IR source. The shroud is vented to allow solvent vapour to exit due to evaporation during the heated centrifuging process. The openings in the shroud are baffled to prevent radiation entering the enclosure. The shroud is made up of two parts which fit over the well plate and co-operate with the support and each other to form the radiation free enclosure around the well plate.

I claim:  
     
         1 . A shroud adapted to fit over a sample holder within a centrifugal evaporator, the shroud being formed from a material which is impervious to UV, and/or visible and/or IR radiation.  
     
     
         2 . A shroud according to  claim 1  which is formed from a plastics material, or aluminium or stainless steel.  
     
     
         3 . A shroud according to  claim 1  characterised in that it is formed in two parts which are adapted to fit from opposite sides of the sample holder to form a radiation free enclosure therearound.  
     
     
         4 . A centrifugal evaporator when fitted with a shroud according to  claim 1 , comprising a rotatable sample support in a chamber, the support having a base on adapted to receive least one sample holder containing liquid sample material, an IR source located so as to direct radiation onto the base during centrifuging to heat the base and thereby heat liquid sample material in the holder by conduction from the base, and wherein the shroud is fitted to the support and serves to prevent any of the IR radiation from impinging directly onto the sample holder.  
     
     
         5 . A centrifugal evaporator according to  claim 4  which includes a swing support for the sample holder, and the shroud is adapted to fit over the swing support.  
     
     
         6 . A centrifugal evaporator according to  claim 5  characterised in that the shroud includes baffled openings to allow solvent vapour to leave the enclosure formed by the shroud and the support, the baffles serving to prevent radiation from directly impinging on the sample holder.  
     
     
         7 . A centrifugal evaporator according to  claim 4 , characterised by a temperature measuring means for sensing the temperature of at least one of the samples.  
     
     
         8 . A centrifugal evaporator according to  claim 7  wherein the temperature sensing means is in the shroud.  
     
     
         9 . A centrifugal evaporator according to  claim 7  wherein the temperature sensing means is in the support.  
     
     
         10 . A centrifugal evaporator according to  claim 7  characterised in that the shroud is apertured and the temperature sensing means is a probe and the probe is adapted for insertion into and through the aperture in the shroud.  
     
     
         11 . A centrifugal evaporator according to  claim 4  wherein the sample holder comprises at least one microtitre well-plate or tube or vial.  
     
     
         12 . A centrifugal evaporator according to  claim 11  wherein there are at least two microtitre well-plates, stacked one above the other on the support, and temperature sensing means is located in a well in the uppermost plate.  
     
     
         13 . A centrifugal evaporator according to  claim 4  characterised in that a heat transfer plate is provided which is adapted to surround at least a part of a region of the sample holder containing liquid sample material and make to good contact therewith, to allow for the efficient transfer of heat therebetween.  
     
     
         14 . A centrifugal evaporator according to  claim 4  wherein the shroud is a single housing which fits over and co-operates with the sample holder support to form a radiation free enclosure.  
     
     
         15 . A centrifugal evaporator according to  claim 4  wherein the shroud is formed in two parts which are fitted from opposite sides of the support, to co-operate therewith when joined to form a radiation free enclosure therearound.  
     
     
         16 . A centrifugal evaporator according to  claim 4  comprising two jaws between which the sample support pivots about a longitudinal axis, thereby to enable it to swing through up to 90° during centrifuging, the support comprises a base and two upstanding ends between which microtitre well-plates are stacked, and the shroud co-operates with the base and the two upstanding ends to create a radiation free enclosure.  
     
     
         17 . A centrifugal evaporator according to  claim 4  wherein the shroud is constructed so as also to shield the sample holder from radiation reflected or refracted by surfaces within the evaporation chamber.  
     
     
         18 . A centrifugal evaporator comprising a chamber, at least one swinging support rotatable therein and adapted to receive and support at least one microtitre well plate thereon, and an infra red radiation source which is operated during centrifuging to direct radiation towards the support characterised by a removable shroud fitted over the well plate and co-operating with the swinging support to form an enclosure which is impervious to direct penetration of radiation from the said source, but is vented to allow solvent vapour to exit due to evaporation during the heated centrifuging process.